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对母液中Mg2+离子对硼掺入无机碳酸盐沉积的影响进行了研究。通过扫描电子显微镜和X射线衍射确定在Mg存在时生成的无机碳酸盐是低镁方解石。实验发现:溶液的pH值是硼进入碳酸盐的主要控制因素,低Mg2+方解石中硼的浓度从63.91μg?g?1(pH =7.40±0.03)增加到582.41μg?g?1(pH =8.80±0.03)。Mg2+离子严重影响硼进入碳酸盐中的量,在相同实验条件下,硼在低镁方解石中的含量高于无Mg2+方解石中的含量,平均为2.57倍(1.83—3.56倍)。这一结果表明:有Mg2+离子时,硼掺入无机碳酸盐的机制和无Mg2+离子的是不同的。Mg2+离子的存在改变了晶体的形貌。这对利用B/Ca指标恢复深海碳酸盐系统研究有重要影响。“,”Background, aim, and scope B/Ca proxies for the deep ocean carbonate system is an important proxy to evaluate carbon sink in sea. Mg2+ is common element in sea which can effect B/Ca values of marine carbonate.Materials and methods The inlfuence ofMg2+ in a parent solution on boron incorporation in an inorganic carbonate precipitate is studied using a different solubility method technique. The calcium carbonate precipitate is characterized by scanning electron microscopy and X-ray diffraction. The boron concentration of the samplers is analyzed by ICP-AES.Results The calcium carbonate precipitate is conifrmed to be low-Mg calcite. The boron concentrations in the precipitated calcite increased from 63.91μg?g?1 to 582.41μg?g?1 when the artiifcial solution pH values increased from 7.40 ± 0.03 to 8.80 ± 0.03.Discussion The results show that boron uptake by low-Mg calcite is greater than boron uptake by free-Mg calcite grown under nearly identical conditions, and the boron concentration in low-Mg calcite is higher than in free-Mg calcite by 2.57 average time (from 1.83 to 3.56). This result suggests that the mechanism for borate-boron co-precipitation with Mg2+ present is different than without Mg2+ present, and the Mg2+ clearly modifies calcite crystal morphology, as identified in SEM images.Conclusions pH has a signiifcant effect on the incorporation of boron into synthetic carbonate, and the Mg2+ also inlfuence on boron incorporation into calcite precipitate.Recommendations and perspectives The data provide a signiifcant scientiifc basis for B/Ca proxies for the deep ocean carbonate system. It is recommended that the Mg2+ would be consider when using B/Ca proxies.